Just out of curiosity, just a few days ago, I wrote a little script that opens each *.dep file in the tce/optional directory, reads each line and appends the basename of the dep file to a "ped" file for each dependency listed.

In the end, example.tcz.ped will have a list of every extension that depends on example.tcz - kind of the flip side of a dep file (hence the name).

I didn't keep the script around but it was trivial to write. Really, when was the last time I actually deleted anything?

In my testing of both offerings so far, neither choices are accurate. […]As much as I luv oneliner's, it completely missed 5 deps that were listed more than twice

Inconceivable

— The `grep` command basically outputs all lines from *dep files, provided there is no non-ASCII character inside (or that the locale is in accordance with the files' encoding), and provided that busybox' grep behaves as expected.— The `sort` command… sorts this whole list— The `uniq` command, with the -d parameter, points out lines that appear consecutively multiple times (remember that the list is sorted).

Let's make more allowance for encoding mismatches, or for busybox possible differences… Here's another try: